void maildir_child(dir) char *dir; { unsigned long pid; unsigned long time; char host[64]; char *s; int loop; strUCt stat st; int fd; substdio ss; substdio ssout;
sig_alarmcatch(sigalrm);//捕捉时间信号。 if (chdir(dir) == -1) { if (error_temp(errno)) _exit(1); _exit(2); }
pid = getpid();//获取当前的进程号。 host[0] = 0; gethostname(host,sizeof(host)); for (loop = 0;;++loop) { time = now(); s = fntmptph; s += fmt_str(s,"tmp/");/*将"tmp/"拷到s中*/ s += fmt_ulong(s,time); *s++ = '.';/*将时间转化为字符串*/ s += fmt_ulong(s,pid); *s++ = '.'; s += fmt_strn(s,host,sizeof(host)); *s++ = 0; if (stat(fntmptph,&st) == -1) if (errno == error_noent) break; /* really should never get to this point */ if (loop == 2) _exit(1); sleep(2); } str_copy(fnnewtph,fntmptph); byte_copy(fnnewtph,3,"new"); //时间为24小时 alarm(86400); fd = open_excl(fntmptph); if (fd == -1) _exit(1); /////////////////////////////////////////////////// substdio_fdbuf(&ss,read,0,buf,sizeof(buf)); substdio_fdbuf(&ssout,write,fd,outbuf,sizeof(outbuf)); //dtline:邮件头Delivered-To部分 //rpline:邮件头返回路径 //无需"From "头部 if (substdio_put(&ssout,rpline.s,rpline.len) == -1) goto fail; if (substdio_put(&ssout,dtline.s,dtline.len) == -1) goto fail; //将邮件写到文件fd中 switch(substdio_copy(&ssout,&ss)) { case -2: tryunlinktmp(); _exit(4); case -3: goto fail; }
if (substdio_flush(&ssout) == -1) goto fail; //将fd所指文件数据由系统缓冲区写回磁盘正确返回0，错误返回-1 if (fsync(fd) == -1) goto fail; if (close(fd) == -1) goto fail; /* NFS dorks */
if (link(fntmptph,fnnewtph) == -1) goto fail; /* if it was error_exist, almost certainly successful; i hate NFS */ tryunlinktmp(); _exit(0);
fail: tryunlinktmp(); _exit(1); }
/* end child process */ //maildir 格式邮箱的邮件投递，不要锁定 void maildir(fn) char *fn; { int child; int wstat; //#define seek_begin(fd) (seek_set((fd),(seek_pos) 0)) //指向文件0的开头 if (seek_begin(0) == -1) temp_rewind();
switch(child = fork()) { case -1: temp_fork(); case 0: maildir_child(fn);///////////////////////////////////// _exit(111); } //返回子进程fd的结束状态值于wstat中 wait_pid(&wstat,child); //#define wait_crashed(w) ((w) & 127) if (wait_crashed(wstat)) temp_childcrashed(); //#define wait_exitcode(w) ((w) >> 8) switch(wait_exitcode(wstat)) { case 0: break; case 2: strerr_die1x(111,"Unable to chdir to maildir. (#4.2.1)"); case 3: strerr_die1x(111,"Timeout on maildir delivery. (#4.3.0)"); case 4: strerr_die1x(111,"Unable to read message. (#4.3.0)"); default: strerr_die1x(111,"Temporary error on maildir delivery. (#4.3.0)"); } } //mbox 格式邮箱的邮件投递，必须锁定 void mailfile(fn)
char *fn; { int fd; substdio ss; substdio ssout; int match; seek_pos pos; int flaglocked; //到文件0开头 if (seek_begin(0) == -1) temp_rewind(); //打开文件fn fd = open_append(fn); if (fd == -1) strerr_die5x(111,"Unable to open ",fn,": ",error_str(errno),". (#4.2.1)"); //时间信号，30秒 sig_alarmcatch(temp_slowlock); alarm(30); //锁定 flaglocked = (lock_ex(fd) != -1); alarm(0); sig_alarmdefault(); //结尾 seek_end(fd); //pos实际指向文件尾（文件大小） pos = seek_cur(fd);
substdio_fdbuf(&ss,read,0,buf,sizeof(buf)); substdio_fdbuf(&ssout,write,fd,outbuf,sizeof(outbuf)); //dtline:邮件头Delivered-To部分 //rpline:邮件头返回路径 //ufline:mbox 是标准的UNIX邮箱格式, 多个邮件存放在一个独立文件内, 每个邮件由一个"From" 的行开始. //这一行看起来像一个标题字段, 不过那不是标题, 那仅仅是传送代理添加的, 便于邮件读出器可以找到每个邮件开始部分的一个标记. if (substdio_put(&ssout,ufline.s,ufline.len)) goto writeerrs; if (substdio_put(&ssout,rpline.s,rpline.len)) goto writeerrs; if (substdio_put(&ssout,dtline.s,dtline.len)) goto writeerrs; for (;;) {//读一行 if (getln(&ss,&messline,&match,'/n') != 0) { strerr_warn3("Unable to read message: ",error_str(errno),". (#4.3.0)",0); if (flaglocked) seek_trunc(fd,pos); close(fd); _exit(111); } if (!match && !messline.len) break; if (gfrom(messline.s,messline.len)) if (substdio_bput(&ssout,">",1)) goto writeerrs; if (substdio_bput(&ssout,messline.s,messline.len)) goto writeerrs; if (!match) { if (substdio_bputs(&ssout,"/n")) goto writeerrs; break; } } if (substdio_bputs(&ssout,"/n")) goto writeerrs; if (substdio_flush(&ssout)) goto writeerrs; //由缓冲区写回磁盘 if (fsync(fd) == -1) goto writeerrs; close(fd); return;
writeerrs: strerr_warn5("Unable to write ",fn,": ",error_str(errno),". (#4.3.0)",0); if (flaglocked) seek_trunc(fd,pos); close(fd); _exit(111); }
void mailprogram(prog) char *prog; { int child; char *(args[4]); int wstat;
if (seek_begin(0) == -1) temp_rewind();
switch(child = fork()) { case -1: temp_fork(); case 0: args[0] = "/bin/sh"; args[1] = "-c"; args[2] = prog; args[3] = 0; sig_pipedefault(); execv(*args,args); strerr_die3x(111,"Unable to run /bin/sh: ",error_str(errno),". (#4.3.0)"); }
wait_pid(&wstat,child); if (wait_crashed(wstat)) temp_childcrashed(); switch(wait_exitcode(wstat)) { case 100: case 64: case 65: case 70: case 76: case 77: case 78: case 112: _exit(100);
case 0: break; case 99: flag99 = 1; break; default: _exit(111); } }
unsigned long mailforward_qp = 0; //转发邮件，地址在recips中 void mailforward(recips) char **recips; {//struct qmail { // int flagerr; // unsigned long pid; // int fdm; // int fde; // substdio ss; // char buf[1024]; // } ; struct qmail QQt; char *qqx; substdio ss; int match;
if (seek_begin(0) == -1) temp_rewind(); substdio_fdbuf(&ss,read,0,buf,sizeof(buf));
if (qmail_open(&qqt) == -1) temp_fork(); mailforward_qp = qmail_qp(&qqt); qmail_put(&qqt,dtline.s,dtline.len); do { if (getln(&ss,&messline,&match,'/n') != 0) { qmail_fail(&qqt); break; } qmail_put(&qqt,messline.s,messline.len); } while (match); qmail_from(&qqt,ueo.s); while (*recips) qmail_to(&qqt,*recips++); qqx = qmail_close(&qqt); if (!*qqx) return; strerr_die3x(*qqx == 'D' ? 100 : 111,"Unable to forward message: ",qqx + 1,"."); }
void bouncexf() { int match; substdio ss; //#define seek_begin(fd) (seek_set((fd),(seek_pos) 0)) //typedef unsigned long seek_pos //将文件0的指针移到开始位置。 if (seek_begin(0) == -1) temp_rewind(); //给ss附值，ss->x=buf,s->fd = 0;s->op = read;s->p = 0(字节数);s->n = sizeof(buf)(还有的空间) substdio_fdbuf(&ss,read,0,buf,sizeof(buf)); for (;;) { if (getln(&ss,&messline,&match,'/n') != 0) temp_read(); if (!match) break; //判定文件是否结束 if (messline.len <= 1) break; if (messline.len == dtline.len) if (!str_diffn(messline.s,dtline.s,dtline.len)) strerr_die1x(100,"This message is looping: it already has my Delivered-To line. (#5.4.6)"); } }
void checkhome() { struct stat st;
if (stat(".",&st) == -1) strerr_die3x(111,"Unable to stat home Directory: ",error_str(errno),". (#4.3.0)"); if (st.st_mode & auto_patrn) strerr_die1x(111,"Uh-oh: home directory is writable. (#4.7.0)"); if (st.st_mode & 01000) if (flagdoit) strerr_die1x(111,"Home directory is sticky: user is editing his .qmail file. (#4.2.1)"); else strerr_warn1("Warning: home directory is sticky.",0); } //得到文件".qmail"+dash+safeext+dashowner的权限，正确返回0，错误为-1 int qmeox(dashowner) char *dashowner; { struct stat st;
if (!stralloc_copys(&qme,".qmail")) temp_nomem(); if (!stralloc_cats(&qme,dash)) temp_nomem();
if (!stralloc_cat(&qme,&safeext)) temp_nomem(); if (!stralloc_cats(&qme,dashowner)) temp_nomem(); if (!stralloc_0(&qme)) temp_nomem(); if (stat(qme.s,&st) == -1) { if (error_temp(errno)) temp_qmail(qme.s); return -1; } return 0; } //qme文件存在且是一般文件返回1，否则为0 int qmeexists(fd,cutable) int *fd; int *cutable; { struct stat st;
if (!stralloc_0(&qme)) temp_nomem();
*fd = open_read(qme.s); if (*fd == -1) { if (error_temp(errno)) temp_qmail(qme.s); if (errno == error_perm) temp_qmail(qme.s); if (errno == error_acces) temp_qmail(qme.s); return 0; }
if (fstat(*fd,&st) == -1) temp_qmail(qme.s); //S_IFREG表示一般文件 if ((st.st_mode & S_IFMT) == S_IFREG) { if (st.st_mode & auto_patrn) strerr_die1x(111,"Uh-oh: .qmail file is writable. (#4.7.0)"); *cutable = !!(st.st_mode & 0100);//看文件的owner权限是否为可执行的。是*cutable = 1，不是*cutable = 0 return 1; } close(*fd); return 0; }
if (!stralloc_copys(&qme,".qmail")) temp_nomem(); if (!stralloc_cats(&qme,dash)) temp_nomem(); if (!stralloc_cat(&qme,&safeext)) temp_nomem(); if (qmeexists(fd,cutable)) { if (safeext.len >= 7) { i = safeext.len - 7; if (!byte_diff("default",7,safeext.s + i)) if (i <= str_len(ext)) /* paranoia */ if (!env_put2("DEFAULT",ext + i)) temp_nomem(); } return; }
for (i = safeext.len;i >= 0;--i) if (!i (safeext.s[i - 1] == '-')) { if (!stralloc_copys(&qme,".qmail")) temp_nomem(); if (!stralloc_cats(&qme,dash)) temp_nomem(); if (!stralloc_catb(&qme,safeext.s,i)) temp_nomem(); if (!stralloc_cats(&qme,"default")) temp_nomem(); if (qmeexists(fd,cutable)) { if (i <= str_len(ext)) /* paranoia */ if (!env_put2("DEFAULT",ext + i)) temp_nomem(); return; } }
*fd = -1; }
unsigned long count_file = 0; unsigned long count_forward = 0; unsigned long count_program = 0; char count_buf[FMT_ULONG];
void main(argc,argv) int argc; char **argv; { int opt; int i; int j; int k; int fd; int numforward; char **recips; datetime_sec starttime; int flagforwardonly; char *x;
umask(077);//将系统umask值设为077&0777的值。open函数的真正权限为mode&-umask sig_pipeignore();//忽略信号 //将environ空间扩大（加10个字符串位置）错误返回0 if (!env_init()) temp_nomem(); //-n Instead of reading and delivering the message, print a description of // the delivery instructions. (man page) //-N 是默认值 flagdoit = 1; while ((opt = getopt(argc,argv,"nN")) != opteof) switch(opt) { case 'n': flagdoit = 0; break; case 'N': flagdoit = 1; break; default: usage(); } argc -= optind; argv += optind; //将参数拷到相应的变量中。 if (!(user = *argv++)) usage(); if (!(homedir = *argv++)) usage(); if (!(local = *argv++)) usage(); if (!(dash = *argv++)) usage(); if (!(ext = *argv++)) usage(); if (!(host = *argv++)) usage(); if (!(sender = *argv++)) usage(); if (!(aliasempty = *argv++)) usage(); if (*argv) usage(); //目录是以'/'开头的 if (homedir[0] != '/') usage(); if (chdir(homedir) == -1) strerr_die5x(111,"Unable to switch to ",homedir,": ",error_str(errno),". (#4.3.0)"); checkhome(); //将"HOST"和host结合为"HOST="+host，加到environ后面。下同 if (!env_put2("HOST",host)) temp_nomem();//接收地址的域名部分 if (!env_put2("HOME",homedir)) temp_nomem();//用户的主目录 if (!env_put2("USER",user)) temp_nomem();//当前的用户 if (!env_put2("LOCAL",local)) temp_nomem();//接收地址的local部分 //将本地的地址扩展。如local为"dingwenbin",host为pact518.hit.edu.cn,则envrecip为"dingwenbin@pact518.hit.edu.cn" if (!stralloc_copys(&envrecip,local)) temp_nomem(); if (!stralloc_cats(&envrecip,"@")) temp_nomem();
if (!stralloc_cats(&envrecip,host)) temp_nomem(); //将envrecip->s加'Z'拷到foo->s. if (!stralloc_copy(&foo,&envrecip)) temp_nomem(); //#define stralloc_0(sa) stralloc_append(sa,"") //GEN_ALLOC_append(stralloc,char,s,len,a,i,n,x,30,stralloc_readyplus,stralloc_append) //struct stralloc{char *s;int len;int a;},len是s的长度，a是总共分配的空间。 //stralloc_ready(x,n)作用是：x没有分配空间就分配n大小空间。已分配了且空间小于n就扩大空间 //stralloc_readyplus(x,n)作用是：x没有分配空间就分配n大小空间。分配给x的空间小于x->len+n,就扩大空间 if (!stralloc_0(&foo)) temp_nomem(); //将"RECIPIENT"和foo.s结合为"RECIPIENT="+foo.s，加到environ后面。下同 //信封上接收者的地址 if (!env_put2("RECIPIENT",foo.s)) temp_nomem(); //邮件头Delivered-To部分 if (!stralloc_copys(&dtline,"Delivered-To: ")) temp_nomem(); if (!stralloc_cat(&dtline,&envrecip)) temp_nomem(); for (i = 0;i < dtline.len;++i) if (dtline.s[i] == '/n') dtline.s[i] = '_'; if (!stralloc_cats(&dtline,"/n")) temp_nomem();
if (!stralloc_copy(&foo,&dtline)) temp_nomem(); if (!stralloc_0(&foo)) temp_nomem(); if (!env_put2("DTLINE",foo.s)) temp_nomem();
if (flagdoit) bouncexf(); //将"SENDER"和sender结合为"SENDER="+sender，加到environ后面。 // 信封上发送者地址 if (!env_put2("SENDER",sender)) temp_nomem(); //将"RPLINE"和"Return-Path:<"+"SENDER"+sender+">/n"结合后加入environ if (!quote2(&foo,sender)) temp_nomem(); if (!stralloc_copys(&rpline,"Return-Path: <")) temp_nomem(); if (!stralloc_cat(&rpline,&foo)) temp_nomem(); for (i = 0;i < rpline.len;++i) if (rpline.s[i] == '/n') rpline.s[i] = '_'; if (!stralloc_cats(&rpline,">/n")) temp_nomem();
if (!stralloc_copy(&foo,&rpline)) temp_nomem(); if (!stralloc_0(&foo)) temp_nomem(); //邮件头返回路径 if (!env_put2("RPLINE",foo.s)) temp_nomem(); //将"From"+*sender拷到ufline中。*sender为空，则将"From"+"MAILER-DAEMON"拷进去 if (!stralloc_copys(&ufline,"From ")) temp_nomem(); if (*sender) { int len; int i; char ch;
len = str_len(sender); if (!stralloc_readyplus(&ufline,len)) temp_nomem(); for (i = 0;i < len;++i) { ch = sender[i]; if ((ch == ' ') (ch == '/t') (ch == '/n')) ch = '-'; ufline.s[ufline.len + i] = ch; } ufline.len += len; } else if (!stralloc_cats(&ufline,"MAILER-DAEMON")) temp_nomem(); if (!stralloc_cats(&ufline," ")) temp_nomem(); //在ufline后面加上现在时间。 starttime = now(); if (!stralloc_cats(&ufline,myctime(starttime))) temp_nomem();
if (!stralloc_copy(&foo,&ufline)) temp_nomem(); if (!stralloc_0(&foo)) temp_nomem(); //UUCP风格的"From"行它包含消息所参与的UUCP大宗 //路径形式的路由、最后一台接收消息的机器处理消息的时间和日期以及一 //指明从哪台主机接收来的可选部分。由于每个处理过这个消息的系统都会生成这个字段，所
//以它通常包括在信封数据下。 if (!env_put2("UFLINE",foo.s)) temp_nomem(); //到空行的作用是：假如ext为"aa-bb-cc-dd",则依次把"EXT=aa-bb-cc-dd"，"EXT2=bb-cc-dd","EXT3=cc-dd","EXT4=dd"加入 //地址扩展 x = ext; if (!env_put2("EXT",x)) temp_nomem(); x += str_chr(x,'-'); if (*x) ++x; if (!env_put2("EXT2",x)) temp_nomem(); x += str_chr(x,'-'); if (*x) ++x; if (!env_put2("EXT3",x)) temp_nomem(); x += str_chr(x,'-'); if (*x) ++x; if (!env_put2("EXT4",x)) temp_nomem();
if (!stralloc_copys(&safeext,ext)) temp_nomem(); //将safeext中字符串转化为小写的 case_lowerb(safeext.s,safeext.len); for (i = 0;i < safeext.len;++i) if (safeext.s[i] == '.') safeext.s[i] = ':'; //例如host为202.18.236.150,则"HOST2=202.18.236","HOST3=202.18","HOST4=202",加入其中 //接收地址的域名部分 i = str_len(host); i = byte_rchr(host,i,'.'); if (!stralloc_copyb(&foo,host,i)) temp_nomem(); if (!stralloc_0(&foo)) temp_nomem(); if (!env_put2("HOST2",foo.s)) temp_nomem(); i = byte_rchr(host,i,'.'); if (!stralloc_copyb(&foo,host,i)) temp_nomem(); if (!stralloc_0(&foo)) temp_nomem(); if (!env_put2("HOST3",foo.s)) temp_nomem(); i = byte_rchr(host,i,'.'); if (!stralloc_copyb(&foo,host,i)) temp_nomem(); if (!stralloc_0(&foo)) temp_nomem(); if (!env_put2("HOST4",foo.s)) temp_nomem();
flagforwardonly = 0; qmesearch(&fd,&flagforwardonly); if (fd == -1)/*文件没打开*/ if (*dash) strerr_die1x(100,"Sorry, no mailbox here by that name. (#5.1.1)");
if (!stralloc_copys(&ueo,sender)) temp_nomem(); if (str_diff(sender,""))/*sender不空*/ if (str_diff(sender,"#@[]"))/*sender和"#@[]"不同*/ if (qmeox("-owner") == 0) { if (qmeox("-owner-default") == 0) { if (!stralloc_copys(&ueo,local)) temp_nomem(); if (!stralloc_cats(&ueo,"-owner-@")) temp_nomem(); if (!stralloc_cats(&ueo,host)) temp_nomem(); if (!stralloc_cats(&ueo,"-@[]")) temp_nomem(); }/*ueo为local+"-owner-@"+host+"-@[]"*/ else { if (!stralloc_copys(&ueo,local)) temp_nomem(); if (!stralloc_cats(&ueo,"-owner@")) temp_nomem(); if (!stralloc_cats(&ueo,host)) temp_nomem(); }/*ueo为local+"-owner@"+host*/ } if (!stralloc_0(&ueo)) temp_nomem(); //转发的发送人地址 if (!env_put2("NEWSENDER",ueo.s)) temp_nomem();
if (!stralloc_ready(&cmds,0)) temp_nomem(); cmds.len = 0; if (fd != -1) if (slurpclose(fd,&cmds,256) == -1) temp_nomem();
if (!cmds.len)/*假如fd文件中没有内容*/ { if (!stralloc_copys(&cmds,aliasempty)) temp_nomem(); flagforwardonly = 0; } if (!cmds.len (cmds.s[cmds.len - 1] != '/n')) if (!stralloc_cats(&cmds,"/n")) temp_nomem();
numforward = 0;/*检查有几行的第一个字符不是'#','.','/',''*/ i = 0;/*i为每行的开始位置*/ for (j = 0;j < cmds.len;++j) if (cmds.s[j] == '/n') { switch(cmds.s[i]) { case '#': case '.': case '/': case '': break; default: ++numforward; } i = j + 1; }
switch(cmds.s[i]) { case 0: /* k == i */ if (i) break; strerr_die1x(111,"Uh-oh: first line of .qmail file is blank. (#4.2.1)"); case '#': break; case '.': case '/': ++count_file; if (flagforwardonly) strerr_die1x(111,"Uh-oh: .qmail has file delivery but has x bit set. (#4.7.0)"); if (cmds.s[k - 1] == '/') if (flagdoit) maildir(cmds.s + i);/////////////////////////////////////////// else sayit("maildir ",cmds.s + i,k - i); else if (flagdoit) mailfile(cmds.s + i); else sayit("mbox ",cmds.s + i,k - i); break; case '': ++count_program; if (flagforwardonly) strerr_die1x(111,"Uh-oh: .qmail has prog delivery but has x bit set. (#4.7.0)"); if (flagdoit) mailprogram(cmds.s + i + 1); else sayit("program ",cmds.s + i + 1,k - i - 1); break; case '+': if (str_equal(cmds.s + i + 1,"list")) flagforwardonly = 1; break; case '&': ++i; default: ++count_forward; if (flagdoit) recips[numforward++] = cmds.s + i; else sayit("forward ",cmds.s + i,k - i); break; } i = j + 1; if (flag99) break; } //转发的地址数不为0就转发 if (numforward) if (flagdoit)
